ixgbe: fix reading of the buffer returned by the firmware

This patch fixes some issues found in the buffer read portion of
ixgbe_host_interface_command()

- use `bi` as the buffer index counter instead of `i`
- add conversion to native cpu byte ordering on register read
- fix conversion from bytes to dword
- use dword_len instead of buf_len when reading the register

Signed-off-by: Emil Tantilov <emil.s.tantilov@intel.com>
Tested-by: Phil Schmitt <phillip.j.schmitt@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

drivers/net/ethernet/intel/ixgbe/ixgbe_common.c

@@ -3344,7 +3344,7 @@ static u8 ixgbe_calculate_checksum(u8 *buffer, u32 length)
 static s32 ixgbe_host_interface_command(struct ixgbe_hw *hw, u32 *buffer,
 					u32 length)
 {
-	u32 hicr, i;
+	u32 hicr, i, bi;
 	u32 hdr_size = sizeof(struct ixgbe_hic_hdr);
 	u8 buf_len, dword_len;
 
@@ -3398,9 +3398,9 @@ static s32 ixgbe_host_interface_command(struct ixgbe_hw *hw, u32 *buffer,
 	dword_len = hdr_size >> 2;
 
 	/* first pull in the header so we know the buffer length */
-	for (i = 0; i < dword_len; i++) {
-		buffer[i] = IXGBE_READ_REG_ARRAY(hw, IXGBE_FLEX_MNG, i);
-		le32_to_cpus(&buffer[i]);
+	for (bi = 0; bi < dword_len; bi++) {
+		buffer[bi] = IXGBE_READ_REG_ARRAY(hw, IXGBE_FLEX_MNG, bi);
+		le32_to_cpus(&buffer[bi]);
 	}
 
 	/* If there is any thing in data position pull it in */
@@ -3414,12 +3414,14 @@ static s32 ixgbe_host_interface_command(struct ixgbe_hw *hw, u32 *buffer,
 		goto out;
 	}
 
-	/* Calculate length in DWORDs, add one for odd lengths */
-	dword_len = (buf_len + 1) >> 2;
+	/* Calculate length in DWORDs, add 3 for odd lengths */
+	dword_len = (buf_len + 3) >> 2;
 
-	/* Pull in the rest of the buffer (i is where we left off)*/
-	for (; i < buf_len; i++)
-		buffer[i] = IXGBE_READ_REG_ARRAY(hw, IXGBE_FLEX_MNG, i);
+	/* Pull in the rest of the buffer (bi is where we left off)*/
+	for (; bi <= dword_len; bi++) {
+		buffer[bi] = IXGBE_READ_REG_ARRAY(hw, IXGBE_FLEX_MNG, bi);
+		le32_to_cpus(&buffer[bi]);
+	}
 
 out:
 	return ret_val;